So a ton of it really depends on what you are trying to do. Quick flips or hold to see if they explode later on? I look for projects that are aiming to address problems so out of your list I have Stratis (C# development) and Sia (Cloud). DGB on the other hand doesn't really have an aim to address problems. I held it for 2 days and then dumped it once the profits made sense after that citibank presentation.
What I do is look at their reddit, website and try to get a general feel as to what their vision is. Their opening statement is big and this is why I am not sold on digibyte:
That's simply just not good enough anymore. Could I be wrong and see it rise to $1 per coin? Maybe, but I doubt it tbh. I was involved with the DGC group before it was clear that it was just a clear pump and dump and got out before I lost money and their vision looked almost identical.
The alts that have my attention right now are these:
Ethereum (I think
@Spree At Last mentioned it, this might be the new crypto god coin. So many projects are built upon ethereum it is crazy. Bancor ICO just help see the price rise dramatically)
Waves
Monero
Factom
Golem
Wings
Darcrus
Ubiq
Florincoin
Guppy
That altfolio has projects that aim to tackle several problems. Privacy (Monero), Databases (Darcrus), Business (Factom, Stratis etc), Sharing hardware resources (Golem), Dating Apps (Guppy) and one with Florincoin that is associated with the alexandria.io project and only trading at 9 cents per right now. It's also good to try and establish a ceiling for certain projects. For example I think Guppy has great potential, but how high can it really go? My guess is that it might cross the $1 per mark if it is ever able to help a dating app startup get off the ground. Darcrus has a ton of potential, but it is very quiet right now. There is always a risk to lose money, but the first 5 I think are very solid. The bottom 5 are a bit of flyers and recommend monitoring activity over a few weeks before deciding to jump in further.
Place a certain amount among coins you think will do well as you see fit. The idea is to limit the chance of a catastrophic loss crippling your earnings.